JCHAIN and COVID-19: Particularly, illustrated by single‐cell evolving trajectory, 3D‐E/BSC had securely reset senile thymus of aging hosts to remodel core immunity by rearranging naive rhythm to evolve TRGC2+/JCHAIN+NKT clusters to abolish tumoral and viral evasion dynamics with path‐feedbacks of NSCLC and COVID‐19 simultaneously activated, leading to continuous blockade of breakthrough infection of viral‐mutants and long‐term survival in one‐third of terminal patients without adjuvant required.